Vapor condensing clothes dryer with pulsed-flow condenser



Jan. 29, 1963 A. M. STONE 3,075,296

VAPOR CONDENSING CLOTHES DRYER WITH PULSED-FLOW CONDENSER Filed Sept. 28, 1960 2 Sheets-Sheet 1 INVENTOR. FGhi AIDAN M. STONE HIS ATTORNEY Jan. 29, 1963 A. M. STONE VAPOR CONDENSING CLOTHES DRYER WITH PULSED-FLOW CONDENSER 2 Sheets-Sheet 2 Filed Sept. 28, 1960 HIS ATTORNEY United States Patent 3,075,296 VAPOR CONDENSING CLOTHES DRYER WITH PULSED-FLOW CONDENSER Aidan M. Stone, Louisville, Ky., assignor to General Electric Company, a corporation of New York Filed Sept. 28, 1960, Ser. No. 58,935 3 Claims. (Cl. 34-75) This invention relates to a clothes drying machine and more particularly to such machines in which cold water I is flowed down a wall of the drying chamber in the drying operation to condense the moisture extracted from the clothes. It will be understood that by clothes drying machines are meant both clothes dryers and combination washer dryers since my invention may be applied to both, and is in tact described in detail hereinafter as applied to a combination washer dryer.

To obtain good drying results in a machine in which coldwater is flowed down a side of the drying chamber to act as a moisture condensing medium, it is desirable that the cold watercover as large an area as possible. I have found that one effective way of making the water spread out over the wall and thereby provide the desired large condensing area is to cause the water to flow at a relatively high rate; However in the interest of economy, because the drying operation continues for a substantial period of time during which flow takes place, the overall rate of flow must necessarily be kept low.

' Accordingly, it is an object of, my invention to provide an improved arrangement for introducing condensing liquid at a relatively high rate without increasing the total consumption of the liquid.

More specifically, it is an object of my invention to achieve this desired result by providing intermittent condensing liquid flow in which the liquid enters in separated pulses. In this manner, a relatively low inlet flow may be used by briefly storing the water and, then discharging it rapidly onto the wall of the condensing chamber.

A further specific, object of my invention is to achieve the pulsed flow effect by providing a siphon which discharges the cooling liquid from a receptacle into the chamber, the siphon having a flow capacity higher than the flow input to the receptacle.

In carrying out my invention, I provide a clothes dryer which has an imperforate tub with walls defining a drying chamber and with clothes tumbling means disposed within the chamber. The clothes are heated as they tumble within the chamber so as to cause moisture to be extracted therefrom by evaporation. In order to remove this moisture from the air, 1 cause cooling liquid to flow down a portion of the interior of the chamber walls, the moisture being condensed out of the air by contact with the cooling liquid. This latter structure includes a container together with means for introducing cooling liquid into the container at a relatively low rate and a siphon which leads out of the container and which has a flow capacity substantially higher than the rate of flow into the container. With this arrangement, the container fills up gradually, and then when the liquid level rises to the top of the siphon, the siphon discharges the container contents into the chamber at a high rate. In this manner, inseparated pulses, the cooling liquid is introduced. It has been found that this intermittent high fiow achieves a more effective heat transfer between the condensing liquid and the moist air. In addition to the foregoing structure, I make the conventional and necessary provision of suitable means for conducting the cooling liquid and the condensed moistu're out from the chamber to drain.

The particular subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. The in- 3,075,296 Patented Jan. 2 9,

ice

2 vention, however, both as to organization and method of operation, togetherwith runner" objects and advantages thereof, may'best be'understood by reference to the fcllowing description taken'in conjunctionwith the accom- P ny ng drawing-S.

In the drawings, FIGURE 1 is a rear elevational view of a combination washer'washer' drayer in which my new and improved arrangement is used, the view being par tially broken away'and partially in section in ord r to illustrate details;

FIGURE 2 is" a side elevational view of the machine of FIGURE 1 with the side panel removed; and

"FIGURE 3' is an enlarged fragmentary cross sectional view of a portion of- FIGURE 2.

Referring now to FIGURES 1, 2 and 3 and initially more particularly to' FIGURE 1, there is shown a combination clothes washing and drying machine of the domestic type wherein the operating elements of the machine are included in an outer cabinet structure having a central wrap-around section 1. Section 1- is supported on a base and toeboardassembly 2. and carries a separate top 3. on which is supported a backsplash panel 4 which may, as shown, be mounted on posts 5. Control panel 4 is generally'provided-with appropriate devices 6'for'pr'oviding manual. control. of. the various types of washing and drying sequences. Access to the interior. of the machine maybe provided through an opening 7 formed in trap-around section 1, the opening being normally closed during. operation by a suitable door structure (not ing its structural strength, The tub, 9 in similar fashion,

has. an. imperforate substantially cylindrical wall 13, a rear wall 14, and an appropriately formed front wall (not shown), andprovides the washing and drying chamber forthe machine. The basket, is rotatably supported by I a shaft 15, which is secured to double wall 12 and is mounted, in, an elongated bearing 16 supported between rear.wall 14 and an auxiliary rearwall 17 of the tub 9. The tnbandbasket are appropriatelyformed at. their front portions so as to permit access through the. opening 7 into the basket for. the insertion and. removal of. clothes;

This feature is conventional in the art, does not form part of this invention, and is therefore not shown in detail herein.

Referring now, particularly, to FIGURE 1, during the operation of; the machine the basket 8. is drivenfrom an electric motor/1,8. The, drive from the motor to the basket includes a pulley 19 which is. secured to the motor shaft so as. to, rotatewther ewith and overwhich passes a belt 29. Belt/2,0 drives, an adjus'table. sheave assembly 2]. of. the type, which is well known for use in, achieving variable, output speeds from a constant input speed source. The adjustable sheave assembly in turn operates a'belt; 22 to cause, rotation of pulleys 23, and 2.4. I The rotation of pulley, 24 is passed on through a belt 26 to a pulley 25, which is secured on basket shaftlS In this manner, the motor18 may be driven at a'constant speed, and, through the adjustable sheave assembly 2'1, the speed imparted to pulley '25 and basket Sfmay be] a sence 3 of severalhundred r.p.m. may be provided to the basket for elfecting centrifugal extraction of the liquid from the clothes prior to either the heat drying operation or removal of clothes from the container.

The operation of the variable speed drive briefly described above does not form any part of the present invention, and is merely set forth to provide a substantially complete description of an operative machine. A complete detailed description of such a drive is provided, for instance, in Patent 2,950,613, issued on August 30, 1960 to John Bochan and assigned to the General Electric Company, assignee of the present invention.

To heat the clothes during the heat drying portion of the cycle, there is provided within the machine a suitable heater assembly including two heaters which may, for instance, include two heaters 27 and 28. When the heaters are energized during the drying cycle, they operate to heat the basket 9 which, through its rotation, then contacts the clothes to transfer its heat to the clothes. In addition, since the outer cylindrical wall of the basket is provided with perforations 11, the heating elements also heat the clothes through radiation. The heat thus transferred to the clothes causes evaporation of moisture from the clothes so as to effect drying thereof.

Means whereby water is admitted to and discharged from tub 9 during washing operations of the machine include connections 29 and 30 through which hot and cold water is supplied from a suitable source to the machine for the washing operation. A valve controlled by a solenoid 31 admits hot water to the machine and a valve controlled by an opposed solenoid 32 admits cold water to the machine. The hot and cold water valves under the control of the solenoids 31 and 32 discharge through a common conduit 33 and a suitable air gap into a funnel 34 positioned beneath the outlet of conduit 33. As can best be seen in FIGURE 2, funnel 34 leads into a downwardly extending conduit 35 and, as shown in FIGURE 1, conduit 35 is joined at its lower end to a sump 36 formed at the bottom of tub 9 so that the wash water enters the tub from the sump beneath it. A pressure actuated sensing device or water level control 37 controls both solenoids 31 and 32 to provide the proper water level in the machine during the operation. Sensing device 37 is connected to the interior of tub 9 by a suitable line 38 which connects with the tub almost at the bottom thereof at 39 as shown. In addition to the water level control device shown, the machine may be provided with other safety devices for preventing overflow conditions from occurring. However, such mechanisms do not form any part of the present invention and are not shown or further discussed herein.

Vitiated water from washing operations is discharged from the machine through the sump 36 formed at the bottom of tub 9. A suitable discharge hose 40 leads from the sump to the inlet of a pump 41 (FIGURE 2) which may, as shown, be driven directly from motor 18. Pump 41 discharges through a conduit 42 to a valve 43 having a closure member 44 controlled by a solenoid 45. The valve is of a conventional type and is normally open when the solenoid is deenergized; when the solenoid is energized, it holds down member 44 which pivots about pivot 46, and acts to close the valve 43. Thus, pump 41 operates all the time during motor operation, but only when valve 43 is open may it discharge through the valve to a conduit 47 leading to drain. When the valve is closed the operation of the pump is without efiect.

As stated, the illustrated machine is of the type which, during the drying cycle, uses cold water for condensing from the air the moisture which has been extracted by heat from the clothes. The condenser water is admitted to tub 9 through an opening 48 formed in wall 13 of tub 9 substantially above the bottom of the tub, so that the water flows down the lower left Wall 49 (FIGURE 1) of the tub. As shown in FIGURE 2, wall section 49 may have an inverted V-shaped head 52'? formed therein so as to help spread the water out thereby to provide a larger condensing surface to the air in the chamber formed by the tub 9.

The improvement of my invention lies in the particular arrangement for feeding water to the opening 48 so as to cause the water to emerge therefrom rapidly at a high rate of how but intermittently so that the total amount of Water used may be kept down to previous levels even though the rate at which water emerges onto wall portion 49 is substantially higher. The admission of condensing water is controlled by a third solenoid actuated valve controlled by a solenoid 51 which is energized during the drying operation so that the valve passes water at a slow rate which may, for instance, be on the order of /2 gallon per minute in actual practice. The water passes from the valve controlled by solenoid 51 out through a conduit 52 which, as shown in FIGURE 2, leads to an outlet 53 discharging through an air gap into a receptacle 54. The receptacle 54 may be made accessible from the front of the machine by means of a member 55 so that the receptacle may be used for the introduction of a suitable rinse agent during the rinse portion of washing operations. The structure for effecting this is fully described and claimed in Patent 2,887,862, issued on May 26, 1959, to Gresham N. Jennings and assigned to the General Electric Company, assignee of the present invention.

The receptacle 54 is fully shown in FIGURE 3. As can be seen in that figure, the receptacle has positioned therein a siphon 55 which has a short leg 56, positioned so that the opening 57 thereof is adjacent the bottom of the receptacle, and a longer leg 58 with its opening 59 positioned to discharge into a receptacle-like vertical portion 60 of a conduit 61. The receptacle portion 60 in turn is connected at its bottom to a portion 63 of conduit 61 formed as a siphon with a short leg 64 and a longer leg leading down to opening 48 so that water discharged from conduit 61 flows down along wall section 49 of tub 9.

When the water entering receptacle 54 from outlet 53 rises to the level of the top of siphon 55, the siphon 55 becomes primed and starts to pass the water in the receptacle 54 up through leg 56 and down through leg 58 into receptacle 60. The level in receptacle portion 64 rises until it reaches the top of siphon 63, at which time siphon 63 passes the Water down to opening 48 until the level in receptacle 60 fails to cover the inlet of short leg 64, at which time the siphon 63 ceases to be primed and the flow of water therethrough stops.

As the essential feature of my invention, I cause the inside diameter of the siphon 63 to be large enough so that the rate of flow through the siphon and into the tub is substantially larger than the rate at which Water is entering the receptacle portion 60 from container 54 through siphon 55 (and, possibly, excess flow over wall 66 of container 54). By use of this feature, it can be seen that when the water rises to the level of the top of siphon 63, the siphon will rapidly discharge all the water in the receptacle 60 even though water is continuing to enter from siphon 55. Thus, there will be alternate periods during which water is being discharged at a relatively high rate through the siphon 63 and during which the receptacle portion 60 is being filled up to a level at which siphon 63 is primed; during the latter periods there is no how through the siphon 63. i

As a typical example, assume an inlet flow rate of /5 gallon per minute from outlet 53, a siphon 63 having an inner diameter of 0.5 inch, having a short leg 64 two inches in height and a longer leg 65 four and one half inches in height, discharging to opening 48. If the receptacle portion 6% contains 1 cubic inch when siphon 63 becomes primed, then in 0.5 second it is emptied, with the receptacle 60 then taking 0.5 second to be refilled to the priming level /2 gallon/minute being approximately equal to 2 cubic inches per second). As stated, this causes a high rate of flow of liquid down wall 49, and this high rate of flow has been found to cause the liquid to be spread substantially more efficiently over the wall section 49. This in turn has been found to cause a substantially better heat exchange between the warm moisture-laden air and the condensing water.

It will be understood that during the drying operation the valve 43 is maintained open continuously so that, by the same arrangement which discharges wash water during the washing operation, the condensing water and the condensed moisture may be passed out to drain.

It will further be understood that the machine illustrated is of the type which, by means of control 6, may in the usual way be preset so as to cause a complete sequence of washing, rinsing, centrifuging, and drying operations to take place, my invention being particularly limited to the condensation of moisture during the drying operation and thus being useful both in combination washer-dryers of the type illustrated and in machines which are provided only to effect a drying operation.

It will also be clear that my invention may be used in a machine which does not utilize a rinse dispenser of the type described in the Jennings patent simply by having outlet 53 feed directly into receptacle 60 rather than into receptacle 54.

It will be seen from the foregoing that my invention provides a pulsed-flow feed for a condensing system in a clothes dryer whereby the high flow rate suitable for effecting better condensing from the air is achieved without an undesirable increase in the quantity of water consumed for the purpose; the pulse rate may, of course, be different from the precise example given, different rates being readily provided by varying rate of flow into the system, or the diameter or lengths of the siphon parts.

While in accordance with the patent statutes I have described what at present are considered to be the preferred embodiments of my invention, it will be obvious to those skilled in the art that various changes and modifications may be made therein without departing from the invention, and I therefore aim in the appended claims to cover all such changes and modifications as fall within the true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. In a clothes dryer: an imperforate tub having walls defining a drying chamber; clothes tumbling means disposed within said chamber; means for heating clothes being tumbled within said chamber to provide a drying operation by extracting moisture therefrom by evaporation; means for flowing cooling liquid down a portion of the interior of said walls in rhythmic separated pulses during at least part of a drying operation at a frequency sufficient to provide a substantial number of such pulses each minute to condense moisture out of the air contacting the cooling liquid; and means for conducting cooling liquid and condensed moisture from said chamber to drain.

2. In a clothes dryer: an imperforate tub having walls defining a drying chamber; clothes tumbling means disposed within said chamber; means for heating clothes being tumbled within said chamber to provide a drying operation by extracting moisture therefrom by evaporation; means for flowing cooling liquid down a portion of the interior of said walls to condense moisture out of the air contacting the cooling liquid, said flowing means comprising a container, means for introducing cooling liquid into said container at a relatively low rate, and a siphon having a short leg communicating with said container adjacent the bottom thereof and having its long leg communicating with the wall of said chamber substantially above the bottom of said chamber, said siphon having a substantially higher flow capacity than the rate of flow of said introducing means whereby said siphon introduces liquid into said chamber in rhythmic separated pulses during at least a part of a drying operation; and means for conducting cooling liquid and condensed moisture from said chamber to drain.

3. The apparatus defined in claim 2 wherein said clothes tumbling means includes a perforated cylindrical basket and said tub includes a cylindrical wall extending around said basket, said siphon having its long leg communicating with said cylindrical tub Wall.

References Cited in the file of this patent UNITED STATES PATENTS 2,695,460 Clark Nov. 30, 1954 2,717,456 Smith Sept. 15, 1955 2,824,385 Toma Feb. 25, 1958 2,843,943 Geldhof July 22, 1958 2,843,944 Toma July 22, 1958 2,892,335 Gray June 30, 1959 2,899,816 Jacobsen Aug. 18, 1959 

1. IN A CLOTHES DRYER: AN IMPERFORATE TUB HAVING WALLS DEFINING A DRYING CHAMBER; CLOTHES TUMBLING MEANS DISPOSED WITHIN SAID CHAMBER; MEANS FOR HEATING CLOTHES BEING TUMBLED WITHIN SAID CHAMBER TO PROVIDE A DRYING OPERATION BY EXTRACTING MOISTURE THEREFROM BY EVAPORATION; MEANS FOR FLOWING COOLING LIQUID DOWN A PORTION OF THE INTERIOR OF SAID WALLS IN RHYTHMIC SEPARATED PULSES DURING AT LEAST PART OF A DRYING OPERATION AT A FREQUENCY SUFFICIENT TO PROVIDE A SUBSTANTIAL NUMBER OF SUCH PULSES EACH MINUTE TO CONDENSE MOISTURE OUT OF THE AIR CON- 